## Conceptual Physics (12th Edition)

The factor $\gamma$ is $\frac{1}{\sqrt{1-v^{2}/c^{2}}}$. The relativistic formula for momentum, $p = \gamma mv$, is greater than the classical formula $p = mv$. There is an upper limit, c, on the speed of a particle, but $\gamma$ can grow without limit as v approaches c. Therefore, there is no upper limit on either the momentum or the kinetic energy of a particle. As momentum gets larger, so does KE.